Excellent analysis, which can only enhance one's listening experience. I have often considered the complexity with which Scarpia's role is written - for a character frequently written off as a monster, he certainly has some gloriously positive music to sing! Tito Gobbi, the best (understatement) interpreter of the role, discusses aspects of Scarpia's complexity in his book on Italian opera.
What you call "Scarpia's fandango" is an interesting interpretation but incorrect. What it really is is the combined motifs of Scarpia and the Sacristan.
So he goes on for seven minutes about the one theme everybody's familiar with anyway: Scarpia's. Would it have killed him to include Tosca and Mario's themes?
He actually only spends a few seconds on Scarpia, most of it it spent on Angelotti and the Madonna / prayer. I find it better since these are far less obvious.
Just because a work is complex does not mean it is inaccessible. You can listen to an opera like Tosca on so many levels, and certainly do not need a degree in musicology to enjoy it thoroughly. Your anti-elitism is just ignorance.